Chemical Reaction vs. Physical Reaction

Key Differences



Comparison Chart
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Change in Properties
Type of Reaction
Original Matter
Formation of New Product

Energy

Use of Equation

Examples

Chemical Reaction vs. Physical Reaction
A chemical reaction is the type of reaction that causes the change in the internal structure of the substance such that the formation of a new substance takes place, e.g., burning of paper or wood, etc. On the other side, the physical reaction is the type of reaction that causes the change in the physical features of the substance without disturbing their internal structure, e.g., freezing or melting of water.
So, a chemical reaction is a reaction that causes a change in the composition and chemical properties of the reactant. On the other hand, the physical reaction causes a change in the physical properties of the reactant, e.g., color, shape, and size, etc. Thus, a chemical reaction causes the formation of a new product, whereas there is no new product formed during a physical reaction.
A chemical reaction is a type of irreversible reaction, i.e., the original matter cannot recover after the reaction. On the flip side, the physical reaction is a type of reversible reaction, i.e., the original matter can recover after the reaction. Moreover, energy absorbed or evolved during a chemical reaction. On the other side, there is no absorption and evolution of energy during a physical reaction.
What is Chemical Reaction?
A chemical reaction is a type of reaction that causes the chemical transformation of the reactants. Alchemists, first of all, studied chemical transformations in the middle ages. They tried to convert the lead into gold by using lead-copper alloys and lead with sulfur.
During a chemical reaction, two or more reactants combined to make a different or new product. In this type of reaction, bonds between the atoms of the reactants broken down to get them to rearrange to form new compounds. This new product that has obtained after the completion of the reaction cannot be converted into reactants again so, it is known as an irreversible reaction.
During a chemical reaction, a chemical change takes place that changes the chemical properties of the substance and transforms it into a different substance that has different chemical compositions. Some signs of chemical change are an evolution of energy, change in odor, the formation of bubbles, and change in temperature, etc.
Moreover, it also involves the absorption and evolution of energy. It requires specific conditions to start a chemical reaction. Mostly, the rate of a reaction increases with the increase in temperature. It provides more thermal energy to reach the activation energy of the reaction, which is essential to break bonds between the atoms.
A chemical reaction can express in the form of an equation that is called a chemical equation. This chemical equation nominal or symbolic represents the starting compounds or reactants, end products, and reaction situation of the chemical reaction. Sometimes it also represents the intermediate products of the reaction.
Examples
Fireworks, rotting banana, fermentation of grapes, burning of paper or wood, the addition of vinegar into baking soda, bleaching a stain, etc. all are chemical reactions examples. Ones these reactions have completed, they cannot be converted into reactants again.
What is Physical Reaction?
The physical reaction is a type of reaction that causes the molecular rearrangement of the reactants to produce a physical change. These changes are affecting the form of a chemical compound but do not change its chemical composition. So, it only involves the change in physical properties of the reactant, i.e., change of strength, changes to crystal form, change of durability, textural change, size, color, shape, volume, and density, etc.
So, any change in color, shape, or odor represents a physical change. There is no new product formed during a physical reaction. It does not involve any evolution and absorption of energy. Moreover, these types of changes are reversible, i.e., the product can be changed back into the reactants. It cannot express in the form of the equation.
Examples
Molding of clay in a new shape, boiling of water, melting of butter on a warm toast, crumpling of paper, freezing of a juice box in the freezer, Melting of wax, dissolving sugar in water, chopping wood, etc. are the examples of physical reactions. All these changes are reversible, i.e., the reactant can be achieved again.